At present, diamond drill bits are widely used in petroleum exploration and drilling operation. This kind of bit consist of a bit body part and diamond composite sheet cutting tooth, the bit body part is made of sintered tungsten carbide material or is formed by processing a metal material as a substrate, and the diamond composite sheet cutting tooth is brazed to the front end of the cutting face of the blade of the bit. In the drilling process, diamond composite sheet cuts rock and withstands great impact from the rock at the same time. They are prone to impact damage when drilling into a high gravel content formation or a hard formation, resulting in damage to the cutting faces. On the other hand, when drilling in shale, mudstone and other formations, the debris produced by cutting through diamond composite sheet can easily form a long strip shape debris. Due to the large size of this kind of debris, it will easily attach to the blades and body part of the bit to form balling, such that the cutting work faces of the blades of the bit are wrapped and unable to continue working, eventually leading to decrease of mechanical speed, no drill footage and other issues. The day rate is very high during the process of drilling. The replacement of the drill bit in virtue of the poor impact resistance or as a result of the decreased mechanical speed owning to the balling will bring high economic costs, so it has become a top priority to effectively improve the ability of impact resistance and the balling resistance of the drill bit.